Chocolate can boost exercise endurance, says study

Chocolate can enhance exercise performance, according to a new mouse study.

Published in The Journal of Physiology, the study claims the intake of cocoa component flavanol epicatechin, resulted in a greater endurance capacity in mice during exercise.

This is because the component induced structural and metabolic changes in the animals’ skeletal and cardiac muscles, said the scientists from University of California, San Diego.

The majority of science into the potential benefits of cocoa has revolved around cardiovascular benefits of the flavanols (also known as flavan-3-ols or catechins), particularly the monomeric flavanol (-) epicatechin, a class of molecules that are thought to have widespread effects on the body.

Methodology and results

In the study, twenty-five one-year-old male mice were examined over 15 days to examine the effect that epicatechin intake had on factors such as the mice’s exercise performance, muscle fatigue, capillarity and mitochondrial biogenesis.

This was done by examining the animal’s hindlimb and heart muscles.

The mice were randomised into two groups. One group was given small 1 mg liquid doses of epicatechin twice a day and a separate control group of mice drank the same amount in water.

The two epicatechin and water conditions were then split into two further groups, in which half of each condition took part in a light exercise routine.

After 15 days, all four of the groups took part in a much more intensive treadmill exercise.

Significant increases were observed in treadmill performance (50 per cent) and enhanced muscle fatigue resistance (30 per cent) for the epicatechin group, claim the researchers.

According to The New York Times, even the control mice that had lightly exercised grew tired more quickly than the nonexercising mice that had been given epicatechin.

Other findings showed that mice that epicatechin consumption also led to higher mitochondrial activity in the mice’s hindlimbs, said the scientists.

In addition, there were significant increases in skeletal muscle capillarity, they said.

The combination of epicatechin and exercise resulted in further increases in oxidative phosphorylation complexes proteins, mitofilin, porin, and capillarity than the epicatechin condition alone, said the scientists.

Small amounts

However, according to the New York Times, study’s author Dr. Francisco Villarreal said only a very small amount of chocolate consumption was enough to intensify the effects of a workout.

From his group’s mouse data, Villarreal said five grams of dark chocolate daily, or just a sixth of an ounce — about half of one square of a typical chocolate bar — is probably a reasonable human dose.

He said a higher consumption could lessen or even undo any benefits, by overloading the muscles’ receptors or skewing the body’s response.